Bumping internal flow version

Summary:
This is first step In order to investigate issues reported by #1621, this PR will bump our internal flow dep to latest released version.
Closes #1628

Differential Revision: D6832198

fbshipit-source-id: e2a6c34f766e007a3a75a8f55e71921d6ffb1767

package.json

@@ -58,7 +58,7 @@
     "eslint-plugin-react": "^7.3.0",
     "eslint-plugin-relay": "^0.0.8",
     "fbjs-scripts": "^0.8.0",
-    "flow-bin": "^0.59.0",
+    "flow-bin": "^0.64.0",
     "gulp": "^3.9.0",
     "gulp-babel": "^6.1.2",
     "gulp-browserify-thin": "^0.1.5",

src/.flowconfig

@@ -27,4 +27,4 @@ suppress_comment=\\(.\\|\n\\)*\\$FlowFixMe\\($\\|[^(]\\|(\\(>=0\\.\\(2[0-8]\\|1[
 module.name_mapper='ReactDOM' -> 'react-dom'
 
 [version]
-^0.59.0
+^0.64.0

yarn.lock

@@ -2097,9 +2097,9 @@ flat-cache@^1.2.1:
     graceful-fs "^4.1.2"
     write "^0.2.1"
 
-flow-bin@^0.59.0:
-  version "0.59.0"
-  resolved "https://registry.yarnpkg.com/flow-bin/-/flow-bin-0.59.0.tgz#8c151ee7f09f1deed9bf0b9d1f2e8ab9d470f1bb"
+flow-bin@^0.64.0:
+  version "0.64.0"
+  resolved "https://registry.yarnpkg.com/flow-bin/-/flow-bin-0.64.0.tgz#ddd3fb3b183ab1ab35a5d5dec9caf5ebbcded167"
 
 for-in@^1.0.1:
   version "1.0.2"